This invention provides an optical-fiber organizer and splice holding structure within a splice case for field use. The organizer can be of either metallic or non-metallic construction. There are also provisions for strength-member tie-offs to the organizer, or the strength member for each of two cables to be joined may be tied, one to the other, thereby directly by-passing the organizer. Thus, the organizer makes possible the orderly and systematic storage of a reserve length of optical fibers and simultaneously provides a protected splice area. It is advantageous to use small fiber-optic light conductors because this permits a greater number of transmission circuits for a given cable size.
In practice, generally a Number 26 AWG or Number 28 AWG metal wire has been the smallest size in general use for telephone work. Recently, fiber-optic cable has made a place for itself in the communication-cable market. A fiber-optic cable is made up of a series of fine glass fibers buffered with a plastic and then usually stranded over a central strength member, covered by an outer jacket. Some fiber-optic cables are reinforced with steel, Kevlar, or aluminum tubing, and may also be filled with various water-blocking compounds.
Assuming the right type fiber and a fiber count of 12, with the fiber-optic cable having an outside diameter of 0.300 inch, this cable could replace a wire cable with 225 pair of conductors and having an outside diameter of 2 inches. Because of their small size, fiber-optic cables can also be utilized in much greater lengths than conventional communication cables, thus cutting shipping, handling and installation costs. The real advantage of a fiber-optic cable is the extremely low loss and high bandwidth characteristic of the cable, thus reducing the number of highly expensive repeaters needed along the cable route.
However, there is a difference in joining two sections of fiber-optic cable together, as opposed to metallic-wire cables. The glass fiber contained in the fiber-optic cable cannot just be bunched, tied, wrapped and shoved into a splice case, as with conventional metallic conductors. Small-diameter glass fibers cannot be crimped and bent at sharp angles, or fiber breaks will occur. Glass fibers have memory and always want to return to straight-line position, and it is very difficult to coil and wind glass fibers in a splice case, without fiber damage. This invention makes possible the easy accumulating, storage and handling of reserve fiber length within the splice case. The invention also offers a substantial amount of physical protection to the optical fiber before, during and after the splicing operation, and in the event of splice-case re-entry.
A device is needed at the splice location, for the orderly storage of reserve fiber length to be utilized, for example, in the event of a fiber break. The purpose of this invention is to provide means for novel handling, storage, and accumulation as well as mechanical protection for reserve lengths of individual fibers contained in a splice case at fiber-optic splicing locations.
Other objects, features and advantages of the invention will appear or be pointed out as the description proceeds.